Objective:
Genebanks have an urgent mandate to increase efficiency and number of germplasm forms and species within collections. This mandate will be achieved through technologies that prolong germplasm shelf-life, tools that nondestructively detect early changes in viability and genetic integrity, and methods that quantify and compare wild and collected diversity. Through time, genebanked materials must stay fit-for-purpose. PGPRU’s goals are to provide state-of-art genebanking methods that address current needs of genebank operators to manage collections cost-effectively and future needs of users for access to well characterized, diverse collections of living germplasm. To meet this challenge, PGPRU will perform research in the next 5 years that will:
OBJECTIVE 1: DETECT GAPS AND REDUNDANCIES IN GENEBANK COLLECTIONS
Develop and validate methods that integrate statistical genetics and spatial analyses to detect gaps and redundancies in genebank collections, and to estimate and compare the genetic diversity among genebank collections and in situ populations, especially for crop landraces and wild relatives.
• Subobjective 1a. Partition genetic diversity within NPGS collections into
subsets and provide metrics to relate genetic distance among accessions.
• Subobjective 1b. Confirm whether geospatial and climatic data can identify
collection gaps or ecotypes.
OBJECTIVE 2: IMPROVE INITIAL AND LONG-TERM SURVIVAL OF STORED GERMPLASM
Devise or refine tools that enhance the long-term viability of stored germplasm, including clonal propagules, and provide the means for curators to assess and predict the response of germplasm to conventional and cryogenic storage treatments.
• Subobjective 2a: Develop methods to recover vigorous plants from shoot tips.
• Subobjective 2b: Quantify variation of shoot tip response to established
preservation methods of desiccation and liquid nitrogen exposure.
• Subobjective 2c: Quantify variation of dormant bud response to preservation
methods of desiccation and liquid nitrogen exposure.
• Subobjective 2d: Quantify variation of seed response to desiccation and
cooling.
• Subobjective 2e: Quantify interactions between temperature, moisture and seed
longevity.
OBJECTIVE 3. EVALUATE CHANGES IN QUALITY AND GENETIC IDENTITY
Design metrics for monitoring and validating biological quality (viability, health, etc.) of stored and regenerated plant germplasm and assess genetic integrity of germplasm and the genetic shifts that occur during germplasm management.
• Subobjective 3a: Develop new tools to measure initial vigor and detect
aging.
• Subobjective 3b: Assess risks of genetic change during genebanking.
OBJECTIVE 4: LOCATE MASKED DESIRABLE GENES IN CROP WILD RELATIVES
Develop and apply genome annotation methods to evaluate collections of crop land races and wild relatives for genetic diversity in key agricultural traits, so as to enable more effective germplasm curation and to improve access to that diversity for marker-assisted breeding.

Approach:
The Plant Germplasm Preservation Research Unit (PGPRU) has the unique mission of troubleshooting plant genebanking methods to solve the most critical problems of genetic resource collections: keeping germplasm alive, healthy and representative of the source population; describing collection composition; and ensuring stored germplasm meets the needs of diverse users. This 5 year plan describes PGPRU’s strategy to apply creative, multidisciplinary approaches that balance the special requirements of diverse living germplasm (seeds, pollen and explants) with the practical needs of curators and users. Research will provide tools that compare genetic diversity of collections with species diversity extant in the wild; broaden the array and longevity of propagules in storage; assess germplasm health with minimum sample depletion; and account for genebanking effects on the biological and genetic integrity of the sample. Our research efforts will be vital to the overall goal of creating relevant scientific collections to understand, protect and use plant diversity in a changing world.
PGPRU will approach the task of improving genebanking as the challenge of achieving apparently contradictory goals, such as maximizing genetic diversity while minimizing collection size; standardizing preservation treatments for diverse propagules that respond differently; monitoring for signs of deterioration during early storage when few changes are known to occur; maintaining genetic heterogeneity in an agricultural context where quality and uniformity are highly valued; and finding specific alleles of interest that may be masked by the genetic background. In a real sense, these contradictions underscore the complex mission of genebanking.
PGPRU will remain at the forefront of plant repository biology and will continue to play a global role in technology transfer for plant genebank management.